Fall Science Meeting to Feature Tethered Satellite Results

Fall Science Meeting Highlights Tethered Satellite Results

October 15, 1996

Scientists attending the Fall 1996 meeting of the American
Geophysical Union will be treated to three special sessions covering scientific
results obtained from the reflight of the Tethered Satellite System (TSS-1R).
The conference will take place on December 18 and 19 in San Francisco, California.

The TSS-1R science mission was conducted on space shuttle flight STS-75
at the end of February 1996. During the flight, the Tethered
Satellite was deployed to a distance of 12.3 miles (19.7 km) and science
data was collected aboard the satellite, the space-shuttle orbiter, and
from a network of ground stations monitoring the earth's ionosphere.

Five hours of tethered operation yielded a rich scientific data set.
These data include tether current and voltage measurements, plasma particle
and wave measurements, and visual observations for a variety of pre-planned
science objectives. During the flight the conducting tether connecting the
Orbiter to the satellite was severed, and large currents were observed to
be flowing between the satellite and the Orbiter during the break event.

Further scientific data were obtained from the instruments on the satellite
after the break, when the science and NASA support teams were able to capture
telemetry from the satellite during the overflight of NASA tracking stations.

One important finding from TSS-1R has been the high level of current
collected by the satellite at relatively low voltage throughout the deployed
phase of the mission. Surprisingly large currents were also observed during
the tether break and gas releases, indicating important new physics at play.
The three Tethered Satellite sessions at the AGU meeting will cover the
results of data analysis from the mission, important supporting physics
insights from laboratory experiments, theoretical and numerical modeling
of current collection during the mission, and the conclusions of recent
studies on the future use of tethers for science in space.